Drier



W. E. PRINDLE.

DRlER.

APPLlCATlON FILED SEPT. 18. 1919.

Patented 001k. 3, 1922.

want is. rnmnnn, or soreness/onto.

DRIER.

.lpplication'flled September 18, 1919. Serial No. 324,493.

To all whom it may concern:

Be it known that 1, WILLIAM E. PRINDLE, a citizen of the United States, residing at Columbus, in the county of Franklin and State of Ohio, have invented certain new and useful Improvements in Driers, of which the following is a specification.

This invention relates broadly to desiccating machinery, and has articular reference to an improved rotary rier wherein are embodied features of construction which en- I able the drier to readily conform and adapt itself to the type of material being dried, and wherein an improved regulating structure is provided for controlling thepassage of heat through the drier so that the application of the heat may be placed in contact with material in such manner as to effect its complete drying without burning:- or otherwise injuring the same. Another object of the invention residesin the provision ot'a drier wherein is embodied a rotatably mounted outer cylinder, through which the material to be dried is adapted to pass, and to provide cooperative mechanism for et tecting the introduction of heat into and around said cylinder at points contiguous to its material receiving end or at its delivery or discharge end, said means being of such character as to direct the heat, derived from a suitable furnace, through a plurality of divided passageways, whereby in the event of the discharge of material which is insutliciently dry, said means may be actuated to pass the directheat of the furnace into engagement with the material at the discharge end of the cylinder, so that the excess moisture may be quickly removed, or in the event of the material being discharged in anv overly dry condition, said furnace heat may be diverted so as to pass in a tortuous manner around-the material so that said heat will be appreciably lessened and the temperature of the material thereby raga-- lated. e 1

With these and other objects in view, as will appear as the description proceeds, the invention accordingly consists in the novel features of construction, combination of elemerits and arrangement cit p arts, hereinafter to be fully described and to have the scope thereof indicated in the following claims.

In the accompanying drawings: Figure 1 is a vertical sectional view taken through a rotary drier constructed in accordance with the principles of the invention.

Figure 2 is a detail View of the reversible discharge mechanism. 1

Figure 3 is a longitudinal sectional view of amodified form of the invention.

ln the construction of the drier disclosed in Figure 1, the same consists essentially of an outer cylinder 1 which is of circular formation and is slightly inclined in a longitudinal direction. 'A furnace setting 2 is provided and upon the upper walls of which there is mounted a plurality of bearings 3, in which are locatedanti-friction rollers 4:. Annular tires 5 are formed upon the outer periphery of the cylinder and are adapted to be received by the rollers 4, so thatthe cylinder as a whole may be rotatably supported and suitably aligned. A gear 6 is fixedto the cylinder and is disposed to mesh with a pinion 7, the latter being rotated through suitable gearing 8 which in turn is connected with a suitable prime mover, not shown, whereby upon the rotation of the latter, similar'inovement in a reduced degree will be imparted to the cylinder. The inlet or forward'end ot the cylinder is provided with a fixed vapor bonnet 9 which is rigidly supported by means of a hopper structure frame 10 and the forward end of the cylinder is .rotatably journaled within the open side of the bonnet. The hopper 12 islconnected withthe framell and is formed to include a rotary conveyor screw 13, by means of which material to be-dried may be fed into the cylinder'l; A. suction tan it is also connect'ed'withthe bonnet 9 and is employed to relieve the cylinder 1 of vapors arising from the drying material.

In the form at the invention illustrated webs 16.. 'The, torward webzjprevents Inaterial discharged into the torw'ard'end or the inner cylinder from passing'between the inner cylinder and the outer cylinder, and accordingly-directs said-materaalkthrough the inner cylinder. Spiral members 1? are s1tuated in ishe forward endot tne outer cylinderand serve tc'guide thematerial toward the bore of the inner-"cylinder. The latter is preferably provided with a series of cempartments formed by walls 18, the latter operating to efiect a through cascading action of the material in the inner cylinder and also provide an increased carrying surface for the same. From the foregoing it will be seen that the rotation of the outer cylinder will thoroughly agitate the material passing therethrough and through the inner cylinder so that all portions of said material will be presented to the drying surfaces. The discharge ends of the cylinders l and 15 are positioned immediately over a reversible discharge trough 19, which is pivotally' mounted as at 20. By reversin the positions of the trough 19, the same wil discharge material into one or the other of the outlets 21 and 22. H the material should be discharged in a fairly moist condition, the same may be diverted to pass out of the setting 2 by way of the outlet 21, or if in a properly dried'condition, by way of the outlet 22. By virtue of this reversible discharge mechanism, the operator is capable of preventing the commingling of moist ma: terial with the dry material or vice versa.

To eflect the drying of the material as the latter passes through the inner cylinder 15, the setting 2 is formed to include a furnace 23, which may be of any suitable type and formed in the arch 24 of said furnace is a plurality of openings 25 which lead into a chamber 26 formed to surround the forward end of the cylinder 1. And the portions of the cylinder 1 which are located within the chamber 26 are suitably apertured as at 27, whereby the heat or the furnace may be directed from its combustion chamber 28 into the chamber 26 and thence into the space 29 defined between the outer cylinder and the inner cylinder. Upon the operation of the fan 14, this heated air will be drawn longitudinallyof the inner cylinder so that the walls of the latter will be heated and the ma- 'terial contained therein will be correspondingly dried by heat radiation. After passing the full length of the inner cylinder 15, the heated products of combustion are V drawn directly into the inner cylinder where I they come in direct contact with the material passing through said inner cylinder.

However, it will be appreciated that the heated gases will be somewhat reduced in temperature by the time the same directly strike the material being dried, so that the likelihood of the latter becoming scorchedor burned will be reduced to a minimum.

' By circulating throughthe inner cylinder 15 in a direction opposite to the travel of the material therethrough, such vapors as will arise from the material will be caught by the circulating gases and conveyed from the drier by the action of the fan 14.

It hasbeen' found however, that under certain conditions, the radiant heat exercised by the gases upon the outer walls of the cylinder 15 is not always sufficient in the treatment of very moist material to effect a thorough and complete drying of the same to the requisite powdered condition and therefore, the setting 2 is provided with a valved passageway 30 which extends under and longitudinally with the cylinder 1, and said passageway may directly communicate with the combustion chamber28 of the furnace and with the discharge end of the drier. To this end said passageway is provided with a damper 31 which is exteriorly controllable, and is capable under certain conditions of entirely preventing the heat of the furnace from passing through said passageway and to cause the heat to be diverted in its usual path into the chamber 26. However, in the event that the material discharged from the drier is insufliciently dried, the operator adjusts the damper 31 so that the heat from said furnace will not only pass into the chamber 26 but may also pass through the passageway 30 and will then be introduced into. direct contact 'with the material leaving the discharge end of the cylinder 15. By thus causing the direct heat of the furnace, at substantially its highest temperature, to contact with the substantially dry material a thorough and complete drying of said material is brought about. On the other hand, with the passageway 30 closed by means of the damper 31, if the material discharged from the drier is in a too thoroughly dried or scorched condition, the temperature of the drier may be reduced by the opening of air inlet ports 32 which are normally closed by plates '33. It will be apparent that by opening one or more of these plates, cold air may be introduced into the passageway 30 and thence drawn into the cylinder 15 by the action of the fan 14, whereby the temperature of'the' discharged material may be readily governed to control the condition of said material when it is discharged-from the drier.

From the foregoing description, it will be apparent that the present drier comprises a structure by means of which the temperature of the delivered product may be readily controlled-and that the drier will be capable of handling substantially all manner of material and will deliver the same in a properly dried condition, said means being of such character as to readily raise or lower the temperature of the drier in accordance with the properties of the materials being desiccated. Certain of the webs 16 are of course apertured as at 34 so as to permit of the passage of the products of combustion in Iparallelism with the innercylinder 15.

' ,n the form of the invention illustrated in Figure 3, the outer cylinder 46 is rotatably mounted in the usual manner and is provided with the common vapor bonnet 47, suction fan 48 and delivery hopper 49.

In this instance, however, the inner cylinder 50 does not receive the material passing through the drier. In view of this fact, said inner cylinder is mounted axially within the outer cylinder by means of radially disposed tubes 51 which not only serve to support the inner cylinder but also act to establish communication between the interior thereof and the surrounding chamber 52 formed in the furnace setting 5.3, the forward end of the inner cylinder being closed.

It will thus be apparent that heat arising from the furnace 54 will pass through the apertured arch 55 and into the chamber 52, whence said heat or the products of combustion are introduced into the interior of the inner cylinder and pass in a rearwardly and longitudinally directed path, so that the material contained in the outer cylinder and passing between the latter and said inner cylinder will receive the drying effects of the heat radiated from said inner cylinder. 15y this construction, and the same feature is inherent in the other forms, the. heat delivered by the furnace 54 when at its highest temperature will not be brought into direct contact with the material passin through the drier, this being done in or er to avoid burning or scorching of said material, and it is not until after the. temperature of the heat of the furnace has been reduced by radiation that said heat is brought into direct contact with the material. In the majority of materials handled bythe drier, this direct contact of the heat therewith will not be likely to scorch or damage the material. The inner cylinder 50, however, terminates within the outer cylinder and is spaced a considerable distance from the discharge end of the latter, partitions 56 being disposed within said outer cylinder at points beyond the inner cylinder so as to present greater surface to said material. After leavin the discharge mouth of the inner cylin er, the heated gases are conducted forwardly of the outer cylinder by the action of the fan 48 and in this manner serve to remove vapors arising from the material being dried.

The condition of the material discharged from the cylinder 46 may be further regulated, as in the other forms of the invention, by the provision of a passageway 57 which leads from the furnace 54 to the discharge end of the cylinder 46. And this passageway is provided'with an adjustable damper 58, whereby the passage of gases through the passageway 57 may be arrested if desired. Obviously, in order to bring the gases of the furnace into direct contact with the material at higher temperatures than the material ordinarily receives, it is simply necessary to rotate the damper 58 to assume open positions, whereby the heat will be diverted in a proportionate degree from passage intothe chamber 52 into the passageway 57' and thence into direct contact with the material being discharged from the cylinder 46. The usual plate covered ports 59 may be provided in the furnace and passa eway to reduce temperatures if found expe ient.

In view of the foregoing description taken in connection with the accompanying drawing, it'willbe perceived that a drier is provided of an exceptionally efficient nature, and one wherein its heat may be distributed to the. best advantage to secure practical and valuable results. The invention further provides a structure whereby the material discharged from the drier will be in a properly prepared condition, and the structureis of such type as to be readily adjusted to adapt the drier to materials of various characteristics.

What I claim is:

1. In a drier of the character described, a rotatably mounted outer. cylinder, an inner cylinder located within said outer cylinder and in spaced relationship from the latter, means for rotating said cylinders, mechanism situated at one end of said cylinders for effecting the introduction of material to be dried therein, a furnace including a setting whose Walls are apertured contiguous to the inlet ends ofsaid cylinders so as to direct heat initially lengthwise of said cylinders in indirect contact with material passing therethrough and subsequently into direct contact with said material, draft means operating to promote the flow of said heat.

through and around said cylinders, and the walls of said setting being formed to provide a longitudinally extending passageway beneath said cylinders, said passageway establishing communication between said furgace and the discharge ends of said cyliners.

2. In a drier of the character described, a rotatably mounted outer cylinder, an inner cylinder located within said outer cylinder and in spaced relationship from the latter, means for rotating said cylinders, mechanism situated at the forward end of said cylinders for effecting the introduction of material to be dried into said inner cylinder, a furnace including a setting whose walls are apertured to direct heat from said furnace into the space between said cylinders, draft means operating to direct said heat longitudinally of and between said cylinders first in a rearward direction in indirect contact with the material passing through said inner cylinder and then interiorly of said inner cylinder and into direct contact with the material being dried, and the wall of said furnace setting being continued to provide an auxiliary valve passageway capable of permitting the heat of said furnace to initially circulate into direct contact withthe material to be dried.

3. In a drier of the class described, a rotatably mounted cylinder structure, means for introducing the material to be dried into the forward end of said cylinder structure, a furnace including a setting having apertured walls, whereby the heat of said furnace is first led into indirect contact with the material passing through said cyl inder structure and finallyinto direct contact with said material, draft means for effecting the flow and exhaust of said furnace heat through and about said cylinder structure, a setting situated to surround the discharge end of said cylinder structure,

and a conduit leading from said furnace setting to the setting at the discharge end of said cylinder structure.

4Q In a structureas characterized in claim 3 and wherein the conduit is provided with damper .means for controlling the fiow of heat therethrough.

5. In a drier of the character described, the combination with a cylinder structure, means for supporting and rotating said structure, mechanism for effecting the introduction of material to be dried into one end of said cylinder structure whereby upon the rotatioriof the latter said material will pass therethrough, a furnace having walls arranged to surround. the inlet end of said structure, a setting disposed at the discharge end of said structure, and a valved conduit between said furnace and said setting.

6. In a drier of the class described, a rotatably mounted outer cylinder having apertures formed in its forward end, an inner cylinder located within said outer cylinder and in spaced relationship from the latter, means for rotating said cylinders, mechanism situated at the forward end of said cylinders for effecting the introductionof material to be dried into said inner cylinder, a furnace having certain of its walls arranged to surround the apertures formed in the forward end of said outer cylinder, whereby the heat of said furnace will be caused to circulate through said apertures and to flow longitudinally of said cylinders in indirect contact with the material passing through said inner cylinder, draft means for causing a rearward longitudinal flow of heat between said cylinders and a subsequent forward fiow of said heat through said inner cylinder in direct contact with said material,

a setting surrounding the discharge end-of said cylinders, and a valve passageway situated between said furnace and said setting, said valve passageway permitting of an initial direct flow of heat from said furnace into direct contact with the material contained in said inner cylinder.

In testimony whereof I affix my signature.

WILLIAM E. PRINDLE. 

